Power PA with Generator [Archive]

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ninevah

Jul-03-2013, 3:17pm

What experience do you have with using a generator to power a PA system?
Looking for either good or bad results.
As you might guess my band has been offered a gig and told there will be a
commercial grade generator to power our PA.

Thanks in advance for your stories.

mandowilli

Jul-03-2013, 3:46pm

I played an outdoor gig a few years back that provided electric power with a large commercial generator. We played first without incident but the next band, a blues act, lost two high end amps in a haze of blue smoke.

I don't know why we were spared but we did run everything through our rack which included one of those Furman power conditioner protection units. As a habit we always plugged our acoustic amps into that as well. We also were drawing a lot less power than the unfortunate victims.

jim simpson

Jul-03-2013, 4:45pm

I played with a group on a float that had the generator attached over the side of it. It was noisy but we managed to get our sound out to the audience. Nice thing about a parade is that we didn't need more than a couple of songs as we continually had a new audience, lol!

TonyP

Jul-03-2013, 6:20pm

I've played several gigs on gens. Even with a power strip, they can be noisy and cause the system to buzz. Plus you've got to play louder to be heard over them. The last one several years ago was the last one I'll do. It was one of the other guys PA and I don't know if gen broke, or just ran out of gas. Either way it fried his PA head before we could switch it off. He wasn't using even a powerstrip. He didn't even tell them the gen had killed his head. Just the price of doing biz I guess, but it definitely made me wary of ever using one again. And I'll not do it unless there's a clause that says if the gen malfunctions and causes any damage, the venue will replace the broken equipment. YMMV.

Willie Poole

Jul-03-2013, 6:29pm

I have tried playing with a generator a few times using a Bose L-1 system and if the voltage drops below 109 volts the Bose won`t work so we had to improvise and use the monitors as our main speakers...In order to keep the noise from messing things up we placed the generator about 100 feet down over a hill and I guess the loooong extension cord made a voltage drop and we couldn`t use the Bose system....I will keep some of these comments to show the promoters of this show, we play it every year, and maybe they will get some commercial power installed at the stage where we play....

Willie

foldedpath

Jul-03-2013, 7:01pm

The first thing to do, is check with whoever is running the event and find out if the PA and generator are being supplied by a professional, licensed and insured sound company.

Same thing if the generator is supplied by another contractor and you're providing your own sound equipment. Find out if it's a licensed and insured outfit, or someone's Cousin JoeBob dragging out a gennie from his hunting camp. Ask if the venue has passed a local code inspection, or has pulled a temporary event permit involving a code inspection (including the gennie). That will usually give you a clue about whether it's power you want to use, or not.

Assuming it's a legit operation, the next question is how much power does your gear draw? If everything will run off a single household 15 amp circuit without tripping a breaker, then you're probably okay with any reasonable commercial generator that's sized for a 15 amp load. The main thing to watch for is under-voltage, typically caused by an undersized gennie that doesn't have enough mechanical stability (big flywheel) and electronic regulation to keep the voltage steady under surge loads. It's more critical if you're in something like a rock band with kick drum sagging voltage in the amps and subs, but for an acoustic act this shouldn't be a big problem if the generator is reasonably well matched to your power draw.

There are power "conditioners" that include voltmeters, or if you know how to use a separate voltmeter safely with AC current you can check it yourself. I have one of those Furman power supplies with an LED ladder for voltage, which has been useful occasionally in diagnosing house power supply problems.

If you use any digital gear, especially something like a newfangled digital mixer, you might want to make sure the generator has a "true sine wave" output. That's not critical with traditional analog gear, but it can make a difference with some things. With a digital mixer, I'd have it running on a UPS so it never saw the gennie power directly.

Final word of advice (and I'm not a licensed electrician so take all of this with a grain of salt), is don't do the gig if anything about the AC power supply smells fishy. That goes for venues with normal wiring, as well as generators. Be safe, protect your gear, but above all... be safe. AC power can mess you up.

Tim2723

Jul-03-2013, 7:43pm

What he said.

I will never play using a generator again in my life, not even of it's with other peoples equipment.

Andy Miller

Jul-03-2013, 8:13pm

I have no practical information to add, but I'll share this because it's fun. My band played a Climate Cycle event this spring in Chicago, where the sound system was powered by these 8 stationary bikes. You can see the meter in the foreground, letting those pedalers know when they had to step it up!

104097

almeriastrings

Jul-03-2013, 11:00pm

Just to reinforce the need to be very, very careful. The output from some generators is really dirty. Beyond anything a simple power strip conditioner can fix. I have known a few folks who used gear at festivals who then regretted it later: one guy lost pretty much an entire wireless and FX rack, around $18K's worth of gear completely fried. Running those from a large UPS is highly recommended.

Charlieshafer

Jul-04-2013, 6:57am

Love Andy Miller's post. As far as clean, consistent power goes, you need a pretty massive generator to insure that, which would also mean really noisy.

For small set-ups, like a Bose, one great way to do it is with one of the generators that use a converter operating off a couple of car batteries. Our electrician (I'm a contractor by day...) has installed huge versions of these in high-usage trading floor applications, where they'll charge them at night, and run all the computers off the batteries during the day for the clean, non-surgy, 100% reliable power under heavy usage. There are smaller versions of these like this one. (http://www.xantrex.com/power-products/backup-power/xpower-powerpack-1500.aspx)

These are an excellent alternative for the guys who can use one small PA for a Farmer's Market type venue, or for those who really need to be heard (and possibly chased away) when doing those random acts of busking on city streets.

Nevin

Jul-04-2013, 8:58am

I would just add that anybody plugging in should have an outlet tester to make sure all the outlets are properly grounded and have the same polarity (phasing). Outlet testers cost around $5. Here is one: http://www.musiciansfriend.com/pro-audio/american-recorder-technologies-ground-fault-outlet-receptacle-tester?src=3WWRWXGP&gclid=CNfR67H_lbgCFcGe4Aodaz8ARQ&kwid=productads-plaid^34106004122-sku^330266.744@ADL4mf-adType^PLA-device^c-adid^14207119202

Safety First.

mandroid

Jul-04-2013, 12:36pm

Power conditioners would be in the supply circuit before your Gear
this one is quite a door-stop but has capacity to handle a lot of gear load.

http://www.parts-express.com/pe/showdetl.cfm?partnumber=125-105

there are 1U size to have in your own Rack Mount Case..

http://www.parts-express.com/pe/showdetl.cfm?partnumber=248-784

foldedpath

Jul-04-2013, 1:42pm

For small set-ups, like a Bose, one great way to do it is with one of the generators that use a converter operating off a couple of car batteries. Our electrician (I'm a contractor by day...) has installed huge versions of these in high-usage trading floor applications, where they'll charge them at night, and run all the computers off the batteries during the day for the clean, non-surgy, 100% reliable power under heavy usage. There are smaller versions of these like this one. (http://www.xantrex.com/power-products/backup-power/xpower-powerpack-1500.aspx)

These are an excellent alternative for the guys who can use one small PA for a Farmer's Market type venue, or for those who really need to be heard (and possibly chased away) when doing those random acts of busking on city streets.

That Xantrex unit is neat, although a bit heavy at 60 lbs. I have a homebrew version I put together a few years ago, for the kind of wedding gig where we need to play during the ceremony at a beach or woodsy setting, away from AC power.

I like the homebrew modular approach because batteries don't last forever, and this lets me size the battery exactly to the power needed. It also lets me keep the charger separate, so it's less weight to haul around. I screwed the inverter to the top of a plastic battery case, hardwired to the battery inside. It's enough to power the single EV ZXA1 speaker we use for this kind of thing, because I don't like hauling a heavy speaker to these remote wedding locations either. The speaker is just 19 lbs., and we use it with a little A&H Zed-10FX mixer. At the ceremony we're usually only playing for about 20 minutes, so the battery doesn't have to be a large as that Xantrex model.

I've been tempted to try the Roland BA-33 (http://www.roland.com/products/en/BA-330/), because it would be even less total weight to haul to the location, and a faster setup. It can't possibly sound as good as the ZXA-1, with ultra-high efficiency speakers powered by just 8 AA batteries. But for many of these outdoor ceremonies we only need a little subtle reinforcement, not full-blown PA.

OF course for a full-size band playing two hours' of music, we're talking much bigger batteries and inverters. There's a cutoff point where using a gas generator makes more sense.

allenhopkins

Jul-04-2013, 2:06pm

This may sound a bit crude/naive, but I've gotten surprising use out of a Fender AmpCan, with its rechargeable battery power, and a little Behringer EuroRack five-channel board, that runs on two 9v batteries. In a small, not too noisy situation, I've run a trio through it, two vocals and three instruments. The Behringer also provides phantom power with a third battery.

Not claiming either great sound or wide sound dispersal, but when there's no other power source…

I use AmpCans (I have two) multi times when giving seniors' programs, including outdoor gigs like picnics etc. Fender's not making them any more, I guess, but I've used mine hundreds of times, with generally good results.

Charlieshafer

Jul-04-2013, 2:40pm

OF course for a full-size band playing two hours' of music, we're talking much bigger batteries and inverters. There's a cutoff point where using a gas generator makes more sense.

Yup, there are limitations. I like your homebrew version quite a bit. My concept of homebrew was just to build a carrier for the generator, the mixer, the amp, and just roll that around. Obviously, there are limitations on terrain. And, yes, you can only use it for a small mixer/amp combo, and for about an hour or so. So, not for everyone, for sure, but a very easy solution for many applications.

mandroid

Jul-05-2013, 1:22am

did a quick site look .. the BA 33 does show a plug for a bigger external battery..

ninevah

Jul-05-2013, 1:00pm

Thanks for the replies.
Has anyone had any experience with a Honda inverter generator.
Here is what the claim is about these.

HONDA'S MOST POPULAR GENERATOR! The EU2000i, lightweight generator which produces 2000 watts/16.7 amps @ 120V of maximum power. It is super quiet, 53-59 dbA and it's perfect for tailgating, RVing, and other recreational activities. This generator is easy to carry, it weighs less than 47 lbs!! It's very fuel efficient and can run up to 9.6 hrs on 1 gallon of gas. The advanced inverter technology provides reliable power to computers and other sensitive equipment. * This Unit is now 50 state compliant exceeding California EPA C.A.R.B regulations

http://www.wisesales.com/eu2000ia-honda-generator.html?utm_source=GoogleBaseFeed&utm_medium=referral&utm_campaign=GoogleBase&gclid=CL6x95z3mLgCFdKe4AodZ0cAow#.UdcJbhZU2gE

allenhopkins

Jul-05-2013, 2:14pm

Realize, though, OP isn't asking what generator to buy; the venue's supplying the generator, and the question is, "What are the issues involved with hooking one's (expensive) PA gear up to generator power?"

I think several valid ones have been raised, from personal and observed experiences -- many negative.

I'd get the venue to sign an agreement that they'd pick up the cost of any damage to performers' equipment caused by use of non-standard electric power sources. Chances are nothing'll go wrong, but if it does, you want the performance sponsor to be on the hook for the cost of repair/replacement.

Charlieshafer

Jul-06-2013, 7:39am

A couple of things:

First, and quickest, the while I have no experience with that Honda generator, the inverter they use solves the clean power solutions. 53-59 db is pretty quiet for a generator.

As regards the OP's question, sure the thread has morphed a bit, but hardly off-topic. A discussion on generators in a more general format is pretty welcome, as it's a problem many will come across.

I highly doubt any venue will sign any damage agreement. They have enough liability to worry about with virtually everything else, from personal injury (like a person walking across a field from the car to the ticket booth) to food service (you may not be the provider, but you allowed them on the scene), to just about everything else. It is possible that the insurance carried by the supplier of the generator might cover damage, but questions would have to be sent to them.

Some musician wanting them to sign a damage will be met with the response: "Whatever is in the original contract you signed is what's in the contract. Too late for riders." In the real world, you need to insure your own stuff, and usually this means traveling with road-worthy (same as studio un-worthy) gear.

allenhopkins

Jul-06-2013, 11:17am

Good points, Charlie, but I've handled a few artists' contracts where the availability of electric power was specified. Not sure that the source of that power -- normal "grid" vs. generator -- was mentioned, but there definitely were contract clauses that required specific location and wattage of electric power.

If a sponsor is expecting a band to bring their own sound system, rather than supplying one for the event, the band's exposure is increased. For many bands, their PA system is their biggest investment. If it's owned by one of the band members, that person is putting at a minimum, four figures worth of gear onstage. And as I read some of the other posts, it appears that generator power poses more risks for the equipment.

Most contracts have, somewhere in the boilerplate, a catch-all clause about the venue's responsibilities to provide adequate staging. This could be interpreted to cover reliable electric power. Whether the venue will agree to a codicil to the basic contract or not, I'd send them a letter stating that the band expects the sponsor to provide electrical services adequate for the band's use, and that the band will seek reimbursement for any equipment damage caused by improper equipment.

My folk club sponsors a small festival each year, formerly held at Markus Park, a summer camp outside Rochester. Through our own error, we mis-wired a circuit in the performance pavilion, and as a result "fried" an electric keyboard belonging to one of the bands. We replaced the keyboard at our cost, and claimed it against the club's insurance; we were reimbursed (above the deductible) for the replacement. We could have asked the band to play (without their keyboard) and submit a claim to us for the damages, but chose to go the other route. I believe that's the way such problems should be handled.

foldedpath

Jul-06-2013, 11:39am

Agreeing with Charlie here, you won't get any waivers signed. The best thing you can do is ask whether an indoor venue has passed a recent code inspection, or that an outdoor festival has pulled the proper permits, which may include a code inspection for wiring. Some events may require no codes or inspection, it just depends on the local regs. You will likely find tight regs and compliance near urban areas. Out in the countryside, there may be no regulations at all for an outdoor concert (which is why some festivals are located where they are).

You can also ask about the venue's or the event's insurance policy, but you may not get a straight answer. If there is a way for the insurance company to avoid covering damage to your gear, they'll find it. "How do we know your gear wasn't defective when it caught on fire?" and so on.

In most situations, these are just normal risks we take when we take personal or company owned PA gear out to a gig. With experience, you should be able to scope things out, and get a feel for whether your gear is safe to plug in. At minimum, carry one of those little plug-in testers so you can at least spot the most obvious wiring problems at fixed installations. With a generator, you should also have a voltmeter or something like those Furman power strips with a voltmeter to spot sagging voltage problems.

The other side of this is liability. If someone's grandma trips over an exposed extension cord running from the generator to your PA gear and breaks her hip, who gets sued? You, or the venue, or both? Obviously this applies at any event where you're setting up a PA and running cables, but the risk increases when you're more distant from the power source (because it's noisy) and you're running long AC cables over areas with foot traffic.

That's another argument for one of these battery/inverter rigs, if your PA is small enough for that kind of power. You keep it next to the PA gear because it's dead quiet, and you don't have that one additional exposed cable to worry about.

foldedpath

Jul-06-2013, 11:48am

Tim2723

Jul-06-2013, 11:58am

We have the second half of that clause in our contract as well, but I'd never thought about the first one. It's never actually come up for us, but it's a good idea.

Jonathan Reinhardt

Jul-06-2013, 9:41pm

"just one food vendor" -- indeed, or even just a popcorn machine! that's so true. these situations all differ, but all require that you get sharp about electric supply and demand if you are putting your gear on the line.

you probably can get 300 feet (from AC source) before line loss is too severe to operate your gear. DO the math. that may be the most preferable option. it may be less or more for your equipment. (stray power cords and liability to be considered!)

there are no easy answers. I worked one day for a solar provider who powered Toots and the Maytels on a sizable battery bank (but with 1/2 the inverter capacity available that day - minor crisis, but stuff happens) and it worked fine. a bit scary to see what the kick and bass were doing to the system, but it worked fine. and yet They Might Be Giants, who were on next, refused to use the same system. we drew from the nearby AC service and, of course, calculated for line loss. all good, blessed be the power company at times. there WAS a generator option but it was not included in the decision as it was a "solar" provider for the show.

just to say that every band should have a plan, whether it be to accept what is available (not always recommended), take no chances, or provide a competent sound individual who can decide these things and make it work on the spur of the moment - safely.

I repeat, someone (and this is probably you) must always do the math.

again, don't take any chances. I personally will not. there are generators and there are (other) generators, better or worse. quieter is always better, but any one of them still could be the death of your equipment if you are not ready to protect it to the max. a chain of surge protectors/power conditioners if you can. and inverters to make it work above a crude level, if necessary. as a musician, that should be important to you. a variety of inverters are to be found in use, from cheap (basic) to high quality. depending on the situation (beach party or concert) choose or request (if you can) a quality one that will not chop (square) off a sine wave peak and low. these inverters that modify a sine wave (by "rebuilding it" to it's natural form are usually used on larger home solar installations for musical (and other) applications, but often not on small outdoor music shows which depend on somebody's backyard generator..

I ramble, but must say that you need to throw nothing other than your old lunchbox powered PA and semi-retired speakers at that venue that is asking a lot for little return if all they provide is an unspecified generator. there has been good advice and excellent, experienced opinions so far in this thread. I hesitate to add my 2 cents. but I did. all have provided some great ideas that I never would have figured out. so absorb it all, and take no risks.

mandroid

Jul-07-2013, 12:29am

seem to recall Willy Nelson Brought his own Generator just to make sure,
that MacArthur Court at U of Oregon ..
had sufficient power to run the gear for his Show.
It was not a Small Generator..

JimKo

Jul-07-2013, 8:58am

I own a Honda 3000 EU and have lent it out to power a small sound system which consisted of vocals and a key board. It is very quiet and seemed to have a consistent power output. I wouldn't hesitate to use it use it to power my own band equipment.
We have also used other generators with very mixed results through the years. The basic problem with many older models is that they are very loud. If you end up using one of these try digging a pit as far away as you have chord for and placing the generator in it. Cover it if possible. That can really help with the noise.
Probably the worst generator experience came at a Ranch Day celebration in a rodeo arena. When the equipment started smoking I asked the person who provided it if he had used the generator much. He responded "Oh yea, we pump water with it all the time." Most well pumps run off of 220 volts. I guess that is how we learn.

Charlieshafer

Jul-07-2013, 9:12am

Good points, Charlie, but I've handled a few artists' contracts where the availability of electric power was specified. Not sure that the source of that power -- normal "grid" vs. generator -- was mentioned, but there definitely were contract clauses that required specific location and wattage of electric power.

That's true, Allen. Virtually all of our contracts request power as part of their tech rider, and that's even for our provided house PA. There are always keyboards, effects pedals, something requiring clean A/C. I've never had any clause in 20 years though, actually specifying how the power got to the outlet; grid vs. generator. I think the agent's assumption is that if you're booking one of their artists, you know what you're doing. That's a scary concept, of course, as it's up to the agent to do their homework if they're serving their clients well. But, for travel, I think the over-riding safe policy is to travel with stuff that won't kill you if it gets ruined/stolen/crushed.

As a total aside, the funny thing is that mandolin players seem to be more attached to their instruments than just about any other musician's group. You know the players and all their favorite instruments, and you rarely see them without them. Guitar players? Outside of Tony Rice, very few travel with heirloom instruments. We've had many who refuse to travel with anything that costs more than $500, even though you know they have a killer collection at their disposal. Fiddlers/violinists run the gamut, from carrying their babies to not even knowing what they were playing or where they got it.

Jimmy Kittle

Jul-08-2013, 7:39pm

I've ran our pa on generators and had good and bad experiences. Know what you're getting into. What does your system require + 30%. Make sure nothing else is running on the generator. Make sure your power cords are heavy enough so there is no power loss there. Meter the power coming into the equipment before turning it on. If they are using household generators, run away as quick as you can....

mrbook

Jul-10-2013, 3:11pm

I have played an occasional gig with a generator in the past without incident using a small system (all we needed). Last week, I played in a band on a parade float, and the generator had problems. It turned out to just be in the generator, but we were worried that it had damaged the PA head and bass amp. They are okay, but I am more wary of using a generator since that incident.

Our best experience was when we were supplied with a Honda generator. Not sure of the model, but we did not have to compete with the usual generator noise.

Tim2723

Jul-11-2013, 1:32am

As a total aside, the funny thing is that mandolin players seem to be more attached to their instruments than just about any other musician's group. You know the players and all their favorite instruments, and you rarely see them without them. Guitar players? Outside of Tony Rice, very few travel with heirloom instruments. We've had many who refuse to travel with anything that costs more than $500, even though you know they have a killer collection at their disposal. Fiddlers/violinists run the gamut, from carrying their babies to not even knowing what they were playing or where they got it.

The best part of playing the pipe organ is never having to carry the instrument!

Terry Allan Hall

Jul-24-2013, 8:11am

Steve Greer

Jul-29-2013, 10:00am

My band played an outdoor wedding service using 2 Bose L1 PA's and two AT4033 condenser mic's. We powered it with a Honda EU2000 genset. The generator was behind us and the mic's 50 feet but the honda is so quiet you could not hear it at the FOH. It was perfect and it sounded great. The Honda genset never came off idle the whole time we played.